diff --git a/configure b/configure
index 921d4183d..9c63bef05 100755
--- a/configure
+++ b/configure
@@ -23317,39 +23317,29 @@ printf %s "checking whether unsetenv returns void... " >&6; }
 if test ${sudo_cv_func_unsetenv_void+y}
 then :
   printf %s "(cached) " >&6
-else case e in #(
-  e) if test "$cross_compiling" = yes
-then :
-  sudo_cv_func_unsetenv_void=no
 else case e in #(
   e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 $ac_includes_default
-        int unsetenv();
-
 int
 main (void)
 {
 
-        return unsetenv("FOO") != 0;
+        return unsetenv("FOO");
 
   ;
   return 0;
 }
 
 _ACEOF
-if ac_fn_c_try_run "$LINENO"
+if ac_fn_c_try_compile "$LINENO"
 then :
   sudo_cv_func_unsetenv_void=no
 else case e in #(
   e) sudo_cv_func_unsetenv_void=yes ;;
 esac
 fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
-esac
-fi
- ;;
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
 esac
 fi
 { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $sudo_cv_func_unsetenv_void" >&5
@@ -23372,7 +23362,8 @@ else case e in #(
   e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 $ac_includes_default
-int putenv(const char *string) {return 0;}
+      int putenv(const char *string) {return 0;}
+
 int
 main (void)
 {
diff --git a/m4/sudo.m4 b/m4/sudo.m4
index 99ddcaa03..2104ef06b 100644
--- a/m4/sudo.m4
+++ b/m4/sudo.m4
@@ -342,16 +342,12 @@ dnl check unsetenv() return value
 dnl
 AC_DEFUN([SUDO_FUNC_UNSETENV_VOID],
   [AC_CACHE_CHECK([whether unsetenv returns void], [sudo_cv_func_unsetenv_void],
-    [AC_RUN_IFELSE([AC_LANG_PROGRAM(
-      [AC_INCLUDES_DEFAULT
-        int unsetenv();
-      ], [
-        [return unsetenv("FOO") != 0;]
+    [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT], [
+        [return unsetenv("FOO");]
       ])
     ],
     [sudo_cv_func_unsetenv_void=no],
-    [sudo_cv_func_unsetenv_void=yes],
-    [sudo_cv_func_unsetenv_void=no])])
+    [sudo_cv_func_unsetenv_void=yes])])
     if test $sudo_cv_func_unsetenv_void = yes; then
       AC_DEFINE(UNSETENV_VOID, 1,
         [Define to 1 if the 'unsetenv' function returns void instead of 'int'.])
@@ -362,10 +358,10 @@ dnl
 dnl check putenv() argument for const
 dnl
 AC_DEFUN([SUDO_FUNC_PUTENV_CONST],
-[AC_CACHE_CHECK([whether putenv takes a const argument],
-sudo_cv_func_putenv_const,
-[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT
-int putenv(const char *string) {return 0;}], [])],
+  [AC_CACHE_CHECK([whether putenv takes a const argument], [sudo_cv_func_putenv_const],
+    [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT
+      int putenv(const char *string) {return 0;}
+    ], [])],
     [sudo_cv_func_putenv_const=yes],
     [sudo_cv_func_putenv_const=no])
   ])